RFR: 8247995: Avoid use of a mapping function in Permissions.getPermissionCollection

[Claes Redestad]

Hi,

this patch fixes a corner-case performance issue with
Permissions.implies(Permission) by not needing to allocate a mapper
function (or lambda) on each invocation of getPermissionCollection
when there are unresolved permissions present.

Bug:   https://bugs.openjdk.java.net/browse/JDK-8247995
Patch: http://cr.openjdk.java.net/~redestad/8247995/open.00/

Testing: tier1-2

Thanks!

/Claes